Oil turbidity indicator



United States Patent OIL TURBIDITY INDICATOR Albert J. Garey, Los Angeles, Calif., assignor to U. S.

Electrical Motors, Inc., Los Angeles, Calif., a corporation of California Filed Apr. 22, 1957, Ser. No. 654,299

3 Claims. (Cl. 88-14) This invention relates to an indicator for oil turbidity.

Oil gauges are in common use, for example, for lubricant wells provided for vertical motors. The gauges are provided with transparent windows, through which the oil in the well is visible, and the level of the oil can also be seen.

Oil when thus used becomes contaminated or turbid by inclusion of dust or other foreign matters that may be due to wearing of relatively moving parts. Such continually increasing contamination, if long continued, results in deterioration of the lubricating qualities of the oil. Hence, discarding of the old oil and replacement with a fresh supply are essential. Yet it is difficult to determine when it is necessary to do this.

It is one of the objects of this invention to make it possible visually to determine when the oil should be changed.

For this purpose, use is made of comparison or standard units corresponding to the appearance of the lubricant having differing degrees of contamination. These comparison or standard units are conveniently included in the oil gauge, so that by a glance, the degree of contamination of the oil in the oil well can be detected. For example, three standards may be used: one corresponding to fresh oil, another to oil near the tolerable limit of contamination, and another actually at this limit. In this way, a maintenance man may be warned, for example, that the next time he is inspecting the oil gauge he should be prepared to replace the lubricant.

It is accordingly another object of this invention to provide conveniently visual standards for comparison with the appearance of the oil.

It is another object of this invention to provide a simple and inexpensive oil gauge that incorporates these standards so that the body of oil to be inspected is in close proximity to the standards.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of one embodiment of the invention. For this purpose, there is shown a form in the drawings accompanying and forming a part of the present specification. This form will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of this invention is best defined by the appended claims.

Referring to the drawings:

Figure 1 is a fragmentary longitudinal section of the upper portion of a vertical electric motor in which the invention is incorporated;

Fig. 2 is an enlarged fragmentary sectional view illustrating the turbidity indicator; and

Fig. 3 is a front view of the indicator, partly broken away.

An indicator 1 (Fig. l) is shown so mounted as to indicate the oil level 2 of a body of oil 3 in a lubricant well for the bearings of an electric motor. This oil well is formed in the upper part of a stationary frame 4 of the electric motor and extends annularly around the motor shaft structure 7 and its bearings 8. The lower surface of the well is defined by the wall 10 forming part of the frame 4. Stator windings 5 of this motor are diagrammatically indicated as supported by the aid of a frame 6.

The shaft structure 7 extends upwardly through the stationary frame 4 and is rotatably supported by the ball bearing structures 8. Since the specific manner in which the shaft structure is supported is of no importance in connection with the present invention, further details thereof are unnecessary. A sleeve 9 is mounted in the lower wall 10 to define the inner boundary of the annular lubricant well. A conventional top or cover 11 may also be provided for the structure.

At the upper portion of the well there is an aperture 12 which has a flange 13. Telescoping Within this flange is a transparent sight member 14 having a convex exterior surface. This sight member 14 may be formed of glass or other transparent material, such as plastic. It serves to close the aperture 12 as by the aid of a clamp ring 15. This clamp ring 15 engages the external flange 16 of the member 14. It is held in clamping position by a. plurality of machine screws 23 engaging appropriate apertures in the frame 4. The flange 16 is urged against the gaskets 17 between which is located a thin metal wall 18. This metal wall 18 has an upper aperture 19 and a lower aperture 20 to permit the oil 3 to extend into the space defined by the member 14 and thereby act as a baffle plate to aid in keeping the oil relatively quiescent in the region of the sight member 14.

In this way, an observer may determine at a glance whether the oil level is within tolerable limits.

Integrally formed with the member 14 are an upper boss 21 and a lower 'boss 22 (Fig. 3). These bosses extend transversely of the member 14, and their left-hand surfaces as viewed in Fig. 2 are flush with the inner surface of the external flange 16.

These bosses 21 and 22 are provided with slots or grooves 24 for the accommodation of rods 25, 26 and 27, preferably made of glass, or other translucent plastic. These glass rods may be supported in slots 24 by friction. The glass rods may be solid and they are at least partially immersed in the body of oil 3.

The rod 25 has a comparison color or tint substantially identical with that of clean or fresh lubricant. Similarly, rods 26 and 27 may have appearances respectively of turbid oil of successively greater degrees of turbidity. For example, the rod 26 can correspond to the color of the oil which is discolored, but not enough to require immediate replacement; and rod 27 can correspond to the color of oil that should be replaced.

It is a comparatively simple matter to match the color of the body of oil 3 with any one of a plurality of rods 25, 26 and 27 to determine its condition. Accordingly, the maintenance man may know at a glance Whether an oil change is due.

The inventor claims:

1. An oil turbidity indicator for oil contained in a lubricant well, comprising a transparent window member closing a sight aperture located in a wall of said well in an area at least partially below the normal oil level in said well, whereby oil contained in said well can be viewed in its true color through said member, a plurality of comparison elements carried by said member in the space wherein the oil is located and immersed therein, and having different colors corresponding to different degrees of turbidity of the oil, and a bafile plate backing said comparison elements to aid in keeping the oil relav a 3 tively quiescent in the region of said comparison elements, whereby the color of said oil may be readily compared with the .colors of said elements by observation of the oil through said member.

'2. An oil turbidity indicator as set forth in claim 1, wherein said comparison elements are frictionally mounted in slots formed in said member.

3. An oil turbidity indicator for oil contained in a v lubricant well, comprising a transparent window member closing a sight aperture located in a wall of said well in an area at least partially below the normal oil level in said well, whereby oil contained in said well can be viewed in its true color through said member, and a plurality of comparison elements frictionally mounted in slots formed in said member in the space wherein the 4 oil is located and immersed therein, and having difierent colors corresponding to difierent degrees of turbidity of the oil, whereby the color of said oil may be readily compared with the colors of said elements by observation of the oil through said member.

References Cited in the file of this patent UNITED STATES PATENTS 2,037,213 Cannon; Apr. 14, 1936 2,487,238 Hallerberg Nova 8, 1949 2,672,756 White Mar. 23, 1954 V FOREIGN PATENTS 514,133 Great Britain Oct. 31, 1939 999,766 France Oct. 3, 1951 

